1. Field of the Invention
The invention is directed to the field of analytical and immunological testing, and more particularly, to a method for testing organic extracts of organisms, vertebrate and invertebrate tissues, and microorganisms, using synthetic membranes in conjunction with antibody binding assays and antigen-antibody reactions, especially with lipid epitopes (haptens or determinants). The reactions utilize a chromatographic phase in which extracted lipid toxins in a solvent migrate toward mixed antibody coated latex beads provided on a solid phase nylon membrane. The reactions may also involve complex formation by antibody-antigen reactions in the liquid phase. Separation techniques for removing complexes from unbound antigens or antibodies are used.
2. History of the Related Art
The use of latex coated with an antibody for detecting antigens has been known in the clinical art, and especially in the area of visible agglutinative reactions. The procedure is sufficiently specific and sensitive for accurate qualitative and quantitative determinations.
The art has recognized radioimmunoassay, agglutination and enzyme immunoassay, in both direct and competitive binding assays. In the area of latex immunoassay, colored latex beads having specific antibodies bound to their surface, either chemically or by absorption, are used as a tag for antibodies. The so-called dipstick enzyme or chemical immunoassay test is used for rapidly generating qualitative and semi-quantitative information regarding the presence of analytes.
There has long been a need for a rapid and simple to perform procedure for distinguishing edible from potentially toxic fish; in particular, a procedure for detecting ciguatoxins and related low molecular weight polyether marine toxins in fish indigenous to regions where the ecological microflora which cause ciguatera are found. The major source of ciguatoxin is Gambierdiscus toxicus (G. toxicus) discovered in 1977 at Gambier Island, French Polynesia. Ciguatoxin has been determined to be the major cause of ciguatera fish poisoning in the tropical and subtropical regions of the world. Ciguatoxin is a marine polyether which is synthesized by G. toxicus and then proceeds up the food chain through herbivorous fish and carnivorous fish (e.g., amberjacks, jacks, snappers, groupers, moray eels and barracuda). Ciguatoxin-4B (CTX-4B) from G. toxicus is converted to ciguatoxin-1 (CTX-1) in the moray eel liver.
Because more than 24 ciguatoxins (congeners) have been reported, it is unknown whether all species of carnivorous fish associated with ciguatera convert CTX-4B to CTX-1. Thus, a test procedure for analyzing suspect fish flesh should be capable of assessing all congeners and related polyethers, such as maitotoxin, okadaic acid, brevetoxin and palytoxin, although the toxicity of the congeners may vary. These toxins, and especially ciguatoxin and its related polyether congeners, are able to maintain resinous and fatty substances in suspension in water and are highly irritating in their pure form to the skin or mucous membrane.
If ciguatoxin is present in fish tissue or mucous membrane and consumed by humans, it can cause severe ciguatera food poisoning. Such poisoning may cause gastrointestinal, neurological and cardiovascular disorders, and a number of general symptoms. Possible gastrointestinal disorders are vomiting, nausea, stomach pains and diarrhea. Neurological symptoms may include paresthesia and dysesthesia. Cardiovascular effects include bradycardia and tachycardia. General symptoms include taste and vision alteration, itching and weakness, and the most severe general symptoms are muscle aches and joint pains which may persist for months.